Rca ctc-53x

[iong]

Just got a RCA model EX 417WR Remote control tv with CTC-53x Chassis. Uses low voltage focus crt 18VDP22. I have poor focus and not sure how to correct this. There is no focus pot however the wire leading from the focus pin of the crt has three placement positions. One pos. is 0 volts another is 310V and last is 790v. There is a resistor inside the picture tube socket and measures correctly. The 0 volts provides best focus but still out of focus. The high voltage is higher then normal about 22k. There is a strap that can be cut to make high voltage higher according to RCA service guide. Voltage 22k when strap was attached. 25k not straped. Hoping someone can help with this focus problem.
My line voltage is a little high around 123VAC.
Perry